Force-pump mechanism.



E. WOERNER.v

FoRc PUMP MEcHANxsn/l.

APPLICATION FILED JULY 14.1914.

Patented May 15, 1917.

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UNITED seras PATENT-OFFICE.

EUGEN WOERNER, OF STUTTGART, GERMANY, ASSIGNOR T0 TVI-IE FIRM 0F ROBERT BOSCH, 0F STUTTGART, GERMANY.

FORCE-PUMP MECHANISM.

To all whom z't may concern.'

Be it known that I, EUGEN VOERNER, a subject of the Emperor of Germany, residing at Lerchenstrasse 28, Stuttgart, Germany, have invented certain new and useful Improvements in Force-Pump Mechanism; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled inthe art to which it appertains to make and use the same.

In lubricating certain kinds of machinery, like-steam engines and internal combustion engines for example, it is necessary to force oil under high pressure into certain parts, such asthecylinder, whereas oil may be supplied at low pressure to certain other parts, suchas the main bearings. Furthermore, the quantity of high pressure oilrequired is usually small comparedl with the quantity of low pressure oil, and the latter sometimes flows in a continuous circuit from the pump to the parts to be lubricated, and then into the crank case of the engine, from where it is sucked up by the low pressure pump, while the high pressure oil does not return to the pump. Inasmuch as the requirements are so different, it has heretofore been customary for automobiles, motor boats and like installations to provide two independent lubricating systems with individual driving mechanisms therefor, the high pressure pumps capable of developing a pressure of atmospheres or more having a small cylinder bore, and being single acting, and the low pressure pumps capable of developing but 0.5 atmosphere having a comparatively large cylinder bore and being double acting.

The object of the present invention is to consolidate the high and low pressure lubricatingpumps into a single apparatus having a common drive, thereby simplifying the installation and reducing the space and cost. I attain this object in the preferred form of construction by disposing one or more high pressure piston pumps, and one or more low pressure piston pumps, around a common driving shaft, and so constructing the driving connections of the pistons of the pumps and y Specification of Letters Patent.

Application filed July 14, 1914. Serial No. 850,957.

Patented Mayj15,191 7.'

the driving connections of the pistons-of the.

controlling valves therefor, that al single cam on the shaft engages the driving connections of all the pump pistons infone circleto reciprocate them in order,

while a Second camv on the shaft engages all the'driving connections of the controlling valve pistons ina concentric circle to reciprocate them l.in proper time relation. As a further result of `this arrangement, onefor more of the high pressure pumps may be used to supply a quantity of oil from its source directly to the crank case of the engine, from which the low pressure pump or pumps take their supply, to thereby compensate for the quantity of oil that is used up in the main bearings and the other part through which the low pressure oil circulates. v

In the accompanying drawings, illustrating as an example -this preferred embodiment within my invention,

Figure l represents an elevation of the pump mechanism with the casing in section;

Fig. 2 represents a section online 2 2 of Fig. l; and Figs. 3, 4. and 5 represent,-to an enlarged scale, some of the .details of the hi h ressure pum se', e2 e3, etc., of the deg P P a siredv number and of the well known kind are fastened on. the base plate and have their pistons r with the driving connections therefor in the form of yokes y disposed in circular arrangement about the axis of the driving shaft f as a center. Thepistons r of the controlling valves of the high pressure pumps have driving connections in .the form of notches y and are disposed in a circle concentric with the other circle. Although more may be provided, the drawings show one low pressure pump /c of the well known double acting type. The piston s of this pump having a driving connection therefor, in the form of a yoke fm, similar to the other yokes y, is disposed in the Same circle as the high pressure pistons r. Inasmuch as the cylinder bore of the low pressure pump 7c is large compared with that of the high pressure pumps, the pistons s of the controlling valves are arranged inside of the circle passing through the controlling valve pistons 7", but each is provided with a driving connection in the form of a deep yoke m extending for driving engagement into said circle. The driving shaft f is journaled through the base plate b and is driven by the worm gearing g.

and extends within the yokes y of the high ypressure pumps and also within the yoke m of the low pressure pump, so as tov have driving engagement with all the high and low -pressure pumps to reciprocate the pistons in order. Likewise, the cam disk i is fastened on the driving shaft and extends into the notches y and also into the yokes a, so as to have driving engagement with all of the controlling valves of the high and low -pressure pumps to reciprocate the pistons thereof in proper time relation with respect t0 the pump pistons. v

If the radial distance between the centers yof the pistons r and r" of the high pressure pumps be denoted by 791, and if the corresponding radial distance for the low pressure pump be denoted by p2, then the depth of either yoke m beyond theccenter of the corresponding piston s" is- ZzpL-py lObviously, the same result would be attained by locating the controlling valve,pistons s in the circle of the controlling valve pistons 1 and then arranging the pistons of the low pressure pump outside of the circle of the pistons 7' of the high pressure pumps by the distance Z; or by offsetting the pistons s as well as the piston s by distances equal in the aggregate to the distance Z. In all of these cases, however, the driving connections of the offset pistons must have the proper driving engagement with the cam disk. It is also apparent that the high pressure pumps may be double acting, or

'that the low pressure pump may be single acting, if desired.

, The operation of the consolidated pump `mechanism hereinbefore described is as follows: During rotation of the driving shaft j, the high-pressure pump pistons 7^, and valso the low-pressure pump pistons s are reciprocated by reason of the driving engagement between the actuating surfaces of the cam disk It and the contact surfaces of the yoke driving connections y-and m; and similarly the controlling valve pistons 1 and s are then reciprocated by reason of the driving engagement between the actuating surfaces of the cam disk z' and the con- 'tact fsurfaces fz/ and m. The elevated and depressed portions of the cam disks h and i are so arranged that the cycle of the pump pistons is displaced 90 from the cycle of the corresponding valve pistons. Thus The inclined cam disk 71, is fastened on the shaft discharge conduit to the place to be lubricated and oilis simultaneously sucked into the cylinder above the piston through the left hand branch of the inlet conduit as shown by the full line arrows. On the upstroke of the pump piston, during which the valve pistons move to their uppermosty position and then return 'to their half way positions, the oil is sucked into the cylinder below the pump piston and is forced out of the cylinder from above the piston, as indicated by the dotted arrows. lIn this way, the low-pressure pump is double-acting and is adapted for discharginglarge quantities of oil at low pressure to the bearingsand other places to be lubricated.

The high pressure pumps are single-acting, and the operation of the valve'mechanism therefor may be of any suitable kind, as for instance similar lto that shown in United States Patent No. 956,016 of April 26, 1910.

I-Iaving thus described my invention, what I claim is:

1. In consolidated highl and low pressure pump mechanism, a single-acting highpressure pump having a pump piston and a valve piston, a double-acting low-pressure pump having a pump piston and two valve pistons, and common driving mechanism for both pumps comprising a rotary shaft, a cam mounted on the shaft in driving en- -gagement with both pump pistons to reciprocate them, and a second cam mounted on the shaft in driving engagement with the valve pistons of both pumps to reciprocate them in suitable relation with the respective pump pistons.

2. In consolidated high and low pressure pump mechanism, a plurality of high-pressure pumps having pump pistons with driving connections disposed in one circle and valve pistons with driving connections disposed in another circle about the same center, a low-pressure pump of large bore hav 120 ing a pump piston with a ,driving connection located in the circle with the driving connections of the high-pressure pump pistons and also having valve pistons with driving connections extending into the circle of the driving connections of the high-pres'- sure pump pistons, and common driving mechanism for all the pumps comprising a shaft rotatable on an axis passingthrough the center of said circles, a cam mounted on 13 the shaft in driving engagement with the In testimony whereof I affix my signadrivng connections of al1 the pump pistons ture, in presence of two Witnesses. to reciprocate them, and a second cam mounted on the shaft in driving engagement EUGEN WOERNER 5 with the driving connections of all the valve Witnesses:

pistons to reciprocate them in suitable re- PAUL WOLFART,

lation With respect to the pump pistons. REINHOLD ELWERT.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, I). 0. 

